|Serine is a nonessential amino acid derived from glycine, and contributes to the formation of cystine from homocysteine. As a
constituent (residue) of proteins, its side chain can undergo O-linked glycosylation. This might be important in explaining some of the devastating consequences of diabetes. It is one of three amino acids residues that is commonly phosphorylated during cell signalling in eukaryotes. Phosphorylated serine residues are often referred to as phosphoserine. Serine proteases are a common type of protease. Serine has sugar-producing qualities, and is very reactive in the body. It is highly concentrated in all cell membranes, aiding in the production of immunoglobulins and antibodies.
Serine can be made in the tissue from glycine (or threonine) so it is nonessential, but its production requires adequate amounts of B3, B6, and folic acid. Serine is important in metabolism in that it participates in the biosynthesis of purines and pyrimidines, cysteine, tryptophan (in bacteria) , in the formation of cell membranes, and in creatine (part of muscle) synthesis. Serine is needed for the metabolism of fats and fatty acids, muscle growth, and a healthy immune system. It aids in the production of immunoglobulins and antibodies, and is a constituent of brain proteins and nerve sheaths. It is important in the production of cell membranes, and muscle tissue synthesis.